Blow vs Draw Reed Gap - Hole 1
I have a new Lee Oskar A blues harp and, as an exercise, I measured the gaps on all the reeds with a set of feeler gauges. Both blow and draw got progressively narrower as the pitches got higher.
But I was surprised to find the 1-hole blow was .37mm, while the draw was only .07, the narrowest gap on the harp. Kinya made a point of adusting the pairs of reeds together in his video, so I was wondering if this is normal, or if blow/draw pairs should be about equal, or what the relationship should be.
PS - the hole plays okay, and I can even bend it (which is saying something)
I'm almost finished gapping an old G harp to your initial spec. Or almost to your spec. My best efforts get me to within .04mm, eg where you spec 0.15mm, I can get to >.011, <0.19. For the first 6 holes, I cam out at .18 .18 .13 .13 .10 and .13 (sorry, trained as scientist, work in mm always). So, not too far from your new recommendation, and it's probably beyond my present ability to get closer without a lot of luck! The blow reeds for those holes came out at .20 .20 .13 .10 .09 .13 -- I was trying to equalize the blow and draw gaps at each hole, because I interpreted your first response to mean that was preferred.
Except for the 8 and 9 draws, the harp plays pretty well with soft breathing. Still messing with those holes.
I bent one reed by dropping a screw into it, but I mamaged to straighten it and it plays well. Probably shortened its life though.
You wrote the wrong millimeter equivalent above for .004", should be 0.010mm.
One further question: do you use the same gaps for high pitch and low pitch diatonics? (eg, a G and a D)
Thanks!
Hello 3PCo, I like your progress.
Have you watched my HARPSMITH Benchcraft YouTube video on this subject? It should make this process easier for you:
https://youtu.be/eI3aS_5HD34?si=n1j7bAupEHeuJTvt
Thanks for catching the conversion error on my DRAW calculations. I posted .004" (0.15mm) and it should have matched my BLOW calculations at .004" (0.10mm). I will make the correction.
0.010mm is also not accurate
As a rule of thumb, harmonicas that have longer weighted reeds will tolerate greater reed offsets (higher gapping). This includes harmonica keys: Low C, Low D, Low Eb, Low E, Low F, Low F#, G (Ab, A)
Your HARPSMITH, Kinya
Yes, I have watched your videos, Kinya. It's what got me started on this.
But I have had to ad-lib a couple of tools. In particular, I found that the Apple pencil is a peachy tool for pressing down on the base of a reed to reduce the gap.
Thanks for catching my typo. Of course, I don't have a 0.01mm feeler gauge!
3PCo
Thanx for the nice tip
Your HARPSMITH, Kinya
Hi Kinya
You might find my new approach to gapping interesting. Or just silly.
https://www.reddit.com/r/harmonica/comments/1gmxebs/visualizing_reed_edge_and_gap_thickness/
Cheers!
3PCo
Impressive set up! Well done 3PCo, but there's more ...
The serious Harmonica Customizer is always vigilant to set up the perfect reed curvature (side profile). This will influence how the reed travels through the reed plate slot--choping up the air and ultimately producing a pitch (e.g. 440 times a second = Concert A). Better the set up, the better the responsiveness of the harmonica.
Operating Principle
The harmonica reed is not a pendulum, but rather a (clock) spring that coils/recoils under pressure, then spring back to a starting point.
Keeping this in mind, sometimes I will trim/adjust the reed thickness from rivet pad to tip to improve reed responsiveness and longevity.
Your HARPSMITH, Kinya
Hello 3PCo, my recommendations are to:
First experiment with the following offsets (gaps):
BLOW & DRAW Reed Plates
Not bad, but you want better response? Then try this:
DRAW Reed Plate only
We (all) know the pitch on the BLOW Reeds are lower for reeds on #1 ~ #6. This means we can further improve bendability by lowering the offsets (gaps) of those six reeds by another .001" (0.025mm):
Let me know how things worked out for you.
Your HARPSMITH, Kinya